Abstract

We analyzed oscillating flow data from U-tube experiments by Lamb et al. (2004) and found that the time-averaged
turbulent kinetic energy (TKE) near bed decreased exponentially with height above the bed in high-density-suspension
(HDS) flows under waves, and that the ratios of TKE distributions in the streamwise, cross-stream, and
vertical dimensions were constant. Based on the finite-mixing-length theory, a semi-theoretical time-averaged
suspended sediment concentration model for HDS was developed. To avoid the stability problems with the numerical
solution, a simplified model was also formulated through combing the apparent Fickian diffusivity and the damping
function. The comparison between the calculated results and measurements shows both models consider the effect of
the sediment-induced stratification well.